This proposal is to continue studies to determine the clinical validity and value of vector magnetocardiography. Specific studies in patients to establish a normal data base for healthy subjects and specific patient subgroups with cardiac disease affecting the ST segment and T waves have been commenced. During the coming year, data collection on specific patient subgroups will be utilized to compare the diagnostic capabilities of vector magnetocardiography with vector cardiography. We expect to be able to determine what additional clinical information can be provided from vector magnetocardiography.